Radio frequency identification (RFID) transponders or tags are well known and come in a wide variety of shapes and sizes. They can be as small as a pencil lead in diameter and one-half inch in length. They can be credit card shaped for combined use with barcode visual inspection applications. RFID tags can also be used for inventory and security purposes. For example, the anti-theft hard plastic tags attached to merchandise in stores are RFID tags.
RFID tags are categorized as either active or passive. Active RFID tags are powered by an internal battery and are typically read/write, i.e., tag data can be rewritten and/or modified, and typically last up to about four years. However, active tags are less desirable in many applications due to their cost, size, and longevity limitations.
Passive RFID tags operate without a separate external power source and obtain operating power from a reader. Passive tags are consequently much lighter than active tags, less expensive, and offer a virtually unlimited operational lifetime. Read-only tags are typically passive and generally are manufactured with a globally unique set of data (usually 32 to 128 bits) that cannot be modified.
RFID-based designs provide for noncontact, non-line-of-sight sensing. Tags can be employed by a vendor for different purposes during the entire life-cycle of the equipment, from manufacturing to distribution to sales to deployment to services and finally disposal. Tags can be employed by the customers for a wide range of purposes as well, including site capacity planning, asset management, and protection.
Determining the presence and identification of devices in a rack is desirable. Existing methods rely upon a user connecting a computer or other reading device to each of the devices in the rack individually, and requesting and retrieving the device information from each device individually. Thus, to retrieve the information from each of the devices in a rack is a large and burdensome undertaking. Furthermore, existing methods rely upon the device being powered and continually transmitting, using various communications protocols over a wired or wireless connection, an indicator of its presence at the prescribed physical location.
In view of the foregoing, there is a need for systems and methods that overcome the limitations and drawbacks of the prior art.